Strange pentaquarks and excited $\Xi$ hyperons in ${\Xi }_b^{-}\to J/\psi \Lambda K^{-}$ final states

Abstract

We comment on the recent evidence by the LHCb Collaboration for a structure in the $J/\psi \Lambda$ final state produced in the decay ${\Xi }_b^{-}\to J/\psi \Lambda K^{-}$, with minimal quark content $c\bar{c}uds$.

Comments: To appear in Science Bulletin (2021)